What is this repository for

This repository contains hardware and software for building practical Visible Light Communication system. The PURPLE board is a cape that works with BeagleBone Black embedded computer. With PURPLE, one can send and receive information using visible light.

The hardware design is available in the eagle folder.

What's included

• Firmware running on PRU including both transmitter and receiver
• User-space program to run on embedded Linux environment
• Hardware schematic
• Partlist to assemble your own cape Digi-Key
• PCB ordering OSH Park

Contents

• config/

This directory contains all configuration files used before make.

• docs/

This directory contains all documents and notes used as instructions and tutorials deployed in class.

• example/

This directory contains the userspace program to send and receive msgs through light.

• firmware/

This directory contains the binary files that's going to run on PRU

• pcb/

This directory contains the hardware schematic and the PCB layout as well as the partlists.

• src/

This directory contains the source file that needs to be compiled into the binary file under firmware folder.

• test/

This directory contains the test and debugging file in user space for the PRU source code.

How do I get set up?

• Summary of set up
  1. Hardware
     • Beaglebone Black
     • Purple Cape
     • SD card
     • Micro USB cable
  2. Software
     • BBB Driver[Windows][Mac][Linux]
     • SSH[Windows][Mac/Linux]
  3. Internet Connection (optional)
     • Ethernet Cable (Required physical access to the LAN port of your router/access point)
     • Wireless Dongle

• Configuration
• Dependencies
• Deployment instructions
  1. LED installation.
  2. Photodiode installation.

How to get started

Step 1: Insert SD card to BBB board. Make sure SD card has been flashed with the purple image.

Step 2: Boot Up the BBB board and connect the board to your PC/Laptop. Make sure you have successfully installed the drivers for BBB.

Step 3: SSH to the board. ssh [email protected]

ssh [email protected]

Step 4: When you login, Change to root.

sudo -s

Step 5: Go to purple repository.

cd purple

Step 6: Reload the pru remoteproc kernel module.

rmmod pru_rproc

modprobe pru_rproc

Step 7: Compile the code.

make clean
make

Step 8: Make sure the code got compiled succesfully.

Step 9: Start listening on incoming messages on one purple board.

cd example
./receive

Step 10: Start sending the messages on other purple board.

cd example
./send "hello world"

Step 11: Make sure the message got received correctly.

Step 12: Congratulations. You've completed this short tutorial.

Who do I talk to?

• Shengrong Yin ([email protected])
• Omprakash Gnawali ([email protected])

References

Exploring Beaglebone

PRU-ICSS

PRU-software-support-package

spruhv7a

arduino VLC

PRU mailing list

BeagleScope

PRUDAQ